OK, Looking at both my 55.2 and 58, (both 6400 models) the rear hose on the 55.2 is the BH4497 (or Napa UP4497) and is on the passenger side. The rear hose on my 58 is on the driver side and is the BH4000 (or Napa UP4000). The 4000 is longer and the frame end has external threads for a nut instead of slots for a keeper.
